S&W M66-8, 2 3/4" .357 Mag and some chrono results.

[Paul105]

Thought this might be of interest.

Labradar Muzzle Velocity (familiariztion run)
60 Deg F
S&W M66-8 2.75" .357 Mag

130gr Fed Hydra-Shok JHP "Personal Defense" PD357HS2 H …….. 1,416 fps avg (84 fps ES) -- two rounds
140gr Underwood Xtreme Penetrator (Philips head mono metal).. 1,422 fps avg ( 5 fps ES) -- two rounds
158gr Horn Xtp - 15.0gr A2400 Std small pistol, new Starline...… 1,316 fps avg (49 fps ES) -- six rounds
165gr CSWCGC (358156) - 13.0gr A2400 New Starline ...… 1,070 fps avg (49 fps ES) -- six rounds
180gr Buff Bore …………………………………………………………………………….. 1,312 fps avg ( 6 fps ES) -- two rounds
185gr LFNGC (Beartooth), 15.0gr Lil'Gun, CCI 400 New Starline.. 1,228 fps avg (14 fps ES) – two rounds
200gr WLNGC (leadheads), 13.4gr H110, Fed 205, New Starline.. 1,102 fps avg ( 4 fps ES) – two rounds

200gr WLNGC (leadheads) handload with Lil Gun ………………………. 1,266 fps avg ( 2 fps ES) -- two rounds
Load data not given -- maybe too much of a good thing. Spent cases fell from chambers, and no obvious signs of over pressure. Recoil was heavy. Don't even know if this stabilizes.

Also ran two Buff Bore 180s thru 16" Rossi M92 carbine ……………. 1,894 fps avg ( 6 fps ES) -- two rounds

Larger sample would change results but probably not a great deal.

Originally bought the 200gr LFNGC Leadheads to load in my Ruger Maximum. Got curious, so loaded some in the .357 mag. Haven't put any on paper, but no problem hitting various shaped steel plates at 28 yds offhand with the 2 ¾".

Was surprised at velocities from the 2 ¾" bbl.

FWIW,

Paul

 

[cadmike]

Sir , thanks for sharing. My general impression from reading thru your data is those are pretty good velocities from such a short barrel, as you mentioned. I would be interested to see results from a larger sample size.

Very good, thanks.

 

[RDub]

If the Labradar technology is as realistic and accurate as advertised, it will be interesting to see more data coming out and comparing to 'sky screen' instruments..
The Ladradar can give velocity readings at various points along the bullet path starting at the muzzle, all the way to the target, yes? So you could obtain readings, say 15' from the muzzle to compare with what a sky screen might show?
Us skyscreen users would be most interested in seeing readings at 15' or so we could compare apples with apples so to speak..

Anyway thanks for the post.. Looking forward to more..

 

[Nevada Ed]

The Lil'Gun data is an eye opener........... !!

Nice to see such low ES with the large 200gr bullets.
How did they do against the 140gr Underwood loads in accuracy?

Take care.

 

[alwslate]

I agree with the above comments on velocities. They seem awfully high
for the short barrel length. Would be interesting to see results from a
different type of chronograph.

 

[rockquarry]

Velocities will often vary somewhat from one range session to the next depending on a number of factors. I've used several chronographs over many years, but used an Oehler 35P longer than the others, more than twenty-five years. With the 35P, I'd set the screens approximately 12 feet (eyeballed, not measured) from a gun muzzle, regardless of whether I was using a rifle or handgun.

I began using a LabRadar in early 2018. The figures I obtain with this unit have been close enough to the Oehler 35P numbers that I have no question about the accuracy of either unit. The negligible velocity differences are of no real consequence.

Chronograph at least five rounds and don't concern yourself with extreme spread or standard deviation numbers unless the figures are really wild and / or accuracy is poor.

 

[Paul105]

Yes, velocities looked a bit high to me also. I have a Competition Electronics chronograph and the recently acquired Labradar. I put a known load thru the same gun over both and there is virtually no difference. Gun was a 2 3/4" M69 with 260gr WFNGC and 23.1 gr H110.

The labradar will give velocities at five different ranges out to 125 yds (increment is user selected). You have to align the Labradar with the target to get these measurements. The "sight" is very crude and cone of dispersion appears to be limited. Bottom line was I didn't always get distance readings, and have subsequently deleted the data. I was shooting at a "popper at 75 yards (which is at the base of the backstop).

Here's a couple of ABDOC121Copyright © 2013by Applied Ballistics, LLC. All rights reserved.1Velocity Decay betweenMuzzleand Chronograph

Link:

http://www.appliedballisticsllc.com/Articles/ABDOC121_VelocityDecay.pdf

I thought the above chrono results were interesting. It was never my intention to attribute any degree of precision or to intimate other guns would show the same velos.

I really like the 2 3/4" M66-8 and 99% of my shooting is done with the 165gr SWCGC over 13 gr of 2400. It is predominantly a range gun -- my primarys are a Kahr CW45 and the 2 3/4" M69 .44 mag.

I didn't accuracy test the 140gr Underwood or the 200gr Leadhead. I did shoot some 28 yard steel plates with the 200gr Leadhead and had no trouble hitting them.

Hope some found the info interesting.

Paul

 

[bronco45]

Thanks Paul, always enjoy your adventures with gunpowder. Keep up the good work.

 

[stansdds]

It's an interesting use of doppler radar, but the retail price is a bit steep for me. I'll stick to my ancient, but accurate, Shooting Chrony. Yes, a Shooting Chrony and mine is one of the old, red ones, but mine was blessed with good sensors and seems to be quite accurate.

 

[ArchAngelCD]

Thank you for the data, I know what it takes to collect it.